Go BottomRan out of Diesel filled it up and now it won 039t start
 | Eddie Suckow
Join Date: Posts: 1 
|
2001-06-08 29086
It's a Cub Cadet 7205 with a 3cyl diesel. Ran out of diesel right in the middle of bush hogging so I went to fill up a can with gas. Filled up the tank on the tractor (took all 5 gallons, it was bone dry!) and went to crank it. It wanted to start, kind of studdering then died. Now it just cranks and cranks. Is the fuel system air bound or something. Any way to purge or prime it?Thanks for any tips!!!Big Ed
Reply to |
Quote Reply |
Add PhotoRan out of Diesel filled it up and now it won 039t start
| Don M
Join Date: Feb 2002 Posts: 120 myLocation
|
2001-06-08 29088
You have to bleed it. I don't know the specifics of your system. It may involve loosening the lines at the injectors. I think that is a typical way.
-Don M ....
Reply to |
Quote Reply |
Add PhotoRan out of Diesel filled it up and now it won 039t start
| Eddie Suckow
Join Date: Posts: 1
|
2001-06-09 29099
Thanks! I figured that was what was required. So I guess I need to unscrew the nut holding the fuel line onto each injector. Do I need to crank it while these nuts are loose or do I just open the nuts and then retighten them?
thanks again,
big ed ....
Reply to |
Quote Reply |
Add PhotoRan out of Diesel filled it up and now it won 039t start
| Paul Nakamura
Join Date: Posts: 1
|
2001-06-09 29106
Ed, you need to crank the starter while the injector pipes are loose until fuel sprays out (beware of high pressure fuel spraying out, it can pierce your skin). I'm not familiar with your particular machine, but I'll give you some general tips on bleeding. Most systems are gravity fed to a certain point, (fuel filter or lift pump) pull the hose off and see that fuel comes out. From there you'll need to bleed every component in the system (lift pump, FI pump, injectors and ?) by loosening each fitting (half turn or so) as you work towards the injectors and cranking until fuel comes out.
I think running out of fuel is something you only do once, you'll never want to do it again :-)
Good Luck,
Paul
. ....
Reply to |
Quote Reply |
Add PhotoRan out of Diesel filled it up and now it won 039t start
| Eddie Suckow
Join Date: Posts: 1
|
2001-06-09 29110
She's running now!
There was two bleed screws on the rear glass bowl/filter under the tank. There was one more at the pump on the engine. There was no priming lever or anything like that that I could see, but then I noticed that there was an inline electric pump between the glass bowl and the fuel pump. There was no need to remove the injector lines, it cranked right up after I bled all the air out.
This is definitely something that I will not be doing again! Thanks for the help all!!
Eddie ....
Reply to |
Quote Reply |
Add PhotoRan out of Diesel filled it up and now it won 039t start
| larry
Join Date: Mar 2004 Posts: 0 St.Davids
|
2001-06-10 29122
When you change the fuel filter you will need to open up the bleed screw on the filter bowl also to get rid of air etc.You dont need to crank the engine because its an electronic fuel pump that runs when key is on
I have a 7274 and I had a weird one yesterday
The fuel line was rubbing against the the side shield & it eventually wore a pin hole in the line needless to say I had a real mess had to splice line & bleed at the injector box.So you might want to check your lines up front & make sure there not rubbing I have 330 hrs. on mine ....
Reply to |
Quote Reply |
Add PhotoRan out of Diesel filled it up and now it won 039t start
| JeffM
Join Date: Posts: 1
|
2001-06-11 29136
I ran my 4400 out of fuel last fall when the fuel gauge hung up. In my opinion, the nicest feature of the Yanmar engines in the JD compacts is that they are self-bleeding. Fill it with fuel, crank the engine a few times, and 20-30 seconds later you're off and running again. Why don't other manufacturers add this feature? It seems so valuable to me. Is there a downside, other than increased cost? Or does it require direct vs indirect injection? ....
Reply to |
Quote Reply |
Add PhotoRan out of Diesel filled it up and now it won 039t start
| Eddie Suckow
Join Date: Posts: 1
|
2001-06-11 29150
Thanks for the tip larry.
Not sure why everyone doesn't use the self bleeding method? Once I figured out how to bleed my setup it wasn't too bad. Just had to WALK back to the garage and get a phillips screw driver and a 12mm wrench.
....
Reply to |
Quote Reply |
Add PhotoRan out of Diesel filled it up and now it won 039t start
| Roger L.
Join Date: Jun 1999 Posts: 0
|
2001-06-11 29170
Jeff, I don't know why other manufacturer's don't do those simple things that work so well. Yanmar also uses "thermostart". It is a cheap and easy cold weather starting system that works. Yet some other makes are still putting glow plugs in their engines. It beats me. Don't they ever look? ....
Reply to |
Quote Reply |
Add PhotoRan out of Diesel filled it up and now it won 039t start
| JeffM
Join Date: Posts: 1
|
2001-06-12 29207
Yeah Roger, I forgot about the "thermostart", which I understand is basically a grid that heats the incoming air. Works even after the engine is started to help smooth out a cold engine. Both this and the self-bleed design are differentiators that provide real competitive value in my book. I don't understand why they aren't copied. ....
Reply to |
Quote Reply |
Add PhotoRan out of Diesel filled it up and now it won 039t start
| John Miller, III
Join Date: Posts: 1
|
2001-06-12 29211
Um...don't remember seeing any diesels other than "direct injection" use thermostart, and also haven't seen any other than "indirect injection" use glow plugs... ....
Reply to |
Quote Reply |
Add PhotoRan out of Diesel filled it up and now it won 039t start
| Roger L.
Join Date: Jun 1999 Posts: 0
|
2001-06-12 29216
Close....It does heat the incoming air, but in a more indirect fashion. Thermostart is a tiny diesel reservoir and valve that allows one or two drops of diesel to drip down onto a heating element that is inside the intake manifold. The hot diesel ignites there and the burning gases are sucked into the cylinder when you crank the engine.
They used the system on a lot of their Yanmar brand tractors, but I've heard that not all of the JD/Yanmars have it. Maybe that is because of some other design feature. I don't know of any limitations on the use of thermostart, but there must be some or else everyone would use it. Yanmar used it on all of their own brandname tractors that I have seen. Both on the simple two cylinder motors - which used very basic direct injection, and on the larger and more refined three cylinder motors. Many of the 3 cylinders used a system that Yanmar called a "precombustion chamber". This precombustion design injected the fuel into a holding chamber where it was ignited and from there ignition pressure sprayed the burning fuel through ports into the rest of the cylinder....It was another crafty Japanese design, and reduced the familiar "diesel knock" quite a bit. ....
Reply to |
Quote Reply |
Add PhotoRan out of Diesel filled it up and now it won 039t start
| TomG
Join Date: Feb 2002 Posts: 5406 Upper Ottawa Valley 
|
2001-06-13 29222
Roger: I'm just curious if the Yanmar precombustion chamber is also know as indirect injection on different engines. ....
Reply to |
Quote Reply |
Add PhotoRan out of Diesel filled it up and now it won 039t start
| Roger L.
Join Date: Jun 1999 Posts: 0
|
2001-06-13 29247
Howdy Tom. Hmm...OK, I remember having the same question when I first started learning about diesels. BTW, I ran across a book about Mr. Diesel's life which I plan to check out next time I'm at the library. From the parts that I scanned it looks interesting. I'd say "fascinating"....but then I'd be a motorhead :-)
Direct injection diesels inject a metered dose of fuel directly into the air that is compressed between the piston and the head. The tip of the injector - the spray nozzle - sticks right into the combustion area in a direct injection. Direct injection diesels have a loud diesel knock, but are reliable, simple, and fuel efficient.
The alternative is some sort of precombustion chamber. There are lots of different shapes and they are grouped together as "indirect injection". Basically all have a chamber of from 10% to about half of the total compressed volume. The chamber is connected to the main compression area by pin holes. As the piston comes up, some of the hot air is forced into this chamber whereupon the injector sprays fuel into the chamber. The fuel in the precombustion chamber starts to burn and its own burn pressure forces the burning fuel along with the unburned charge back out of the pin holes into the main compression area where it continues to burn. Precombustion gives a smoother burn without the abruptness of direct injection. So indirect injection engines have less of the famous diesel knock - they are a lot quieter....not that any diesel is very quiet. Indirect injection is usually less fuel efficient and I hear that they are tricky to design. I think we are going to see a lot more of this type in the future.
At idle you can hear the difference in the engines. ....
Reply to |
Quote Reply |
Add PhotoRan out of Diesel filled it up and now it won 039t start
| TomG
Join Date: Feb 2002 Posts: 5406 Upper Ottawa Valley
|
2001-06-14 29255
Roger: My mid-80's Ford 1710, which uses a Shibaura engine, has pre-combustion chambers. I thought it probably is similar to what you described on Yanmar. Clever design, but maybe not as clever as thermostart, which really appeals to me for some reason. I understand that easier starting in cold weather is another benefit if indirect injection. I guess that's because glow plugs are located in the pre-combustion chambers, and they don't have to heat much mass. Come to think of it, I really don't know if direct injection engines have glow plugs. ....
Reply to |
Quote Reply |
Add PhotoRan out of Diesel filled it up and now it won 039t start
| MJB
Join Date: Posts: 1
|
2001-06-14 29258
Here is an excerpt from a diesel fuel reference I found which was written by Chevron.
D I R E C T-I N J E C T I O N A N D I N D I R E C T-I N J E C T I O N
The two fuel injection processes used in diesel engines, direct-injection (DI)
and indirect-injection (IDI), are illustrated in Figures 6-2 and 6-3. In a DI
engine, fuel is injected directly into the cylinder above the piston. In an IDI
engine, fuel is injected into a small prechamber connected to the cylinder via
a narrow passage that enters the prechamber tangentially. During the compres-sion
process, air is forced through this passage, generating a vigorous swirling
motion in the prechamber. Then fuel is injected into the prechamber and igni-tion
occurs there. The combination of rapidly swirling air in the prechamber
and the jet-like expansion of combustion gases from the prechamber into the
cylinder enhances the mixing and combustion of the fuel and air.
The more rapid mixing of fuel and air achieved in IDI engines comes at a price,
however. The high velocity flow of air through the narrow passage connecting
the main cylinder to the prechamber, as well as the vigorous swirling motion
in the prechamber itself, causes the air to lose significantly more heat during
compression than it does in a DI engine. Coupled with a pressure drop from
the main chamber to the prechamber, this results in an air temperature in the
prechamber after compression that is lower than that in a similar DI engine.
Since rapid fuel autoignition requires a certain air temperature, an IDI engine
needs a higher compression ratio to achieve the desired air temperature in
the prechamber. IDI engines operate at compression ratios of about 20:1 to
24:1; while DI engines operate at ratios of about 15:1 to 18:1. The heat losses
that necessitate these higher compression ratios have another, more impor-tant
effect: they decrease the efficiency of the engine. IDI engines typically achieve fuel efficiencies that are 10% to 20% lower, on a relative basis, than
comparable DI engines.
Even with the higher compression ratios, IDI engines may still be hard to start.
Most IDI engines use glow plugs to heat the air in the prechamber in order to
make starting easier. Glow plugs, which are small resistive heaters, are usually
powered for only the first few minutes of engine operation.
With the negative attributes of harder starting and lower efficiency, one may
wonder why IDI diesel engines are used at all. The answer is engine speed. As
an engine gets smaller, generally it must operate at higher speeds to generate
the desired power. As engine speed increases, there is less time per engine
cycle to inject, vaporize, mix, and combust the fuel. As a result, the higher
mixing rates afforded by IDI designs become necessary to achieve good
combustion at higher engine speeds. IDI diesels most commonly are used in
smaller automotive and light duty truck applications.
....
Reply to |
Quote Reply |
Add PhotoRan out of Diesel filled it up and now it won 039t start
| John Miller, III
Join Date: Posts: 1
|
2001-06-14 29264
Hi Tom, You have 1 item backwards, Indirect injection diesels are much harder cold starting...not easier. The fuel economy is 10 - 20% better on a direct injection engine. I believe most all farm tractors I've ever seen are direct injection. If you notice, all the Kubota's, New Holland's, Massey Ferguson, Long, & Kioti compact tractors are indirect and all the Kubota/NH/MF larger utility class and farm/ag size are direct injection. John Deere across the board currently has all direct injection {except 4100}, and this includes Yanmar and JD Powertech engines. The only "thermostart" heater(12v. heater coil) reference{I've seen} is used in the air intake system to preheat the incoming air for helping under 32 degree starts. Maybe they have used the term "thermostart" for something else as Roger has suggested. ....
Reply to |
Quote Reply |
Add PhotoRan out of Diesel filled it up and now it won 039t start
| Roger L.
Join Date: Jun 1999 Posts: 0
|
2001-06-14 29281
Well Tom, it looks like John and I agree on everything except ease of starting. I think the indirect starts easier. But I think we all agree that diesels start easily enough if you simply keep everything right and use a heater....as you should on any engine. As for the glowplug, you have a misconception that it lives in the precombustion chamber. It could, but doesn't have to...and usually doesn't. And the flip side of that is about direct injection using glow plugs: Yes, it is common. You need go no farther than the Ford truck dealer. Their 7.3 is direct injection with glow plugs.
As you might have guessed, I'm a fan of indirect injection. I think it is the wave of the future, and recent designs already have solved most (not all) of the fuel problem....at least on smaller engines where the market has the money to favor the big advantage of indirect injection - that they are quieter. I keep expecting to see indirect engines have problems with carboning up the small passages in the precombustion chamber, but I haven't heard of it. Maybe someone more up to date on tractor repair can fill us in. ....
Reply to |
Quote Reply |
Add PhotoRan out of Diesel filled it up and now it won 039t start
| JeffM
Join Date: Posts: 1
|
2001-06-14 29294
Roger and TomG, I agree with John and would deduce that direct fuel injection started easier based on my limited personal experience. The empirical evidence I've seen is that the JD 4000 series starts far easier in cold weather and runs smoother much more quickly than the late model NH and Kubota tractors that I've had the pleasure of trying/operating. Maybe it is the pre-heater instead of the direct injection, but back when I was shopping I started 4400s right up on the dealer's lot at 4 degrees F early on a cloudy morning with only a second or two on the pre-heater. Push the key in (the heater) for a couple more seconds while running and everything smooths out fast. My friend's NH 1720 and several Boomers I've started on dealers lots took a LOT more coaxing to get started in the cold. Same with 2 Kubotas I've tried in the cold. I know this is a limited sample, but like you guys, I live in cold country, and this was one aspect of the tractors I checked out before I bought. Any conflicting observations out there? ....
Reply to |
Quote Reply |
Add PhotoRan out of Diesel filled it up and now it won 039t start
| TomG
Join Date: Feb 2002 Posts: 5406 Upper Ottawa Valley
|
2001-06-15 29300
Thanks guys. Very good information. I've always been sure that this is the best place to be for people who want to understand how their tractors actually work, and this thread is one of the reasons why. Regarding my various deficiencies: I guess I generalized from my single example. The glow plugs for my 1710 are in the pre-combustion chamber. I also succumbed to the risks of thinking--as is common for me. I figured that if composition occurs in the pre-combustion chamber, then it makes sense to heat that particular area. Yes, I'm at risk for turning my thinking into rules and even natural laws--should have been a politician I guess. Regarding cold starting, I probably was comparing apples and oranges--my pre-heated indirect injection with direct injection farm tractors and no pre-heat. Anyway, when I bought the tractor, people kept telling me how much trouble I'd have starting it in the winter. That just didn't happen. -0F starts are two hours on the block heater, 15-30 seconds pre-heat and it takes right off. I do use 0W-30 oil though. I figure these winter-starting horror stories must come from somewhere. Interesting comment about the compression ratios. It reminded me of something I heard. Somewhere I heard about a late 50's engine that could run on gas or diesel. There was a way to change the compression ratio by opening valves to false chambers in the head. I believe this was supposed to be a way to eliminate the 'pony gas' engines that were sometimes used to start diesels at that time. No matter what our opinions on direct vs. indirect injection, I guess we all should be thankful diesel engine design evolved, and that most of us are using modern diesels. ....
Reply to |
Quote Reply |
Add Photo
Go Top
Share This